1. Field of the Invention
This invention relates generally to apparatus for injecting water or other suitable fluid directly into soil to reach the roots of vegetation thereabout and more particularly to an underground irrigation apparatus which can be inserted into ground to be irrigated in a simple and efficient manner.
2. Description of the Prior Art
It has long been known to insert appropriate devices into soil in order to treat the ground as is appropriate for various crops. For example, U.S. Pat. No. 3,762,171, issued Oct. 2, 1973, to I. Byorheim, et al, discloses a ground heater which injects steam into soil being treated in order to thaw the soil. More commonly, however, such apparatus is employed for purposes of direct irrigation of plant roots, and the like, or for fertilizing crops, killing weeds, and the like.
For example, U.S. Pat. No. 749,758, issued Jan. 19, 1904, to W. G. Templeton, discloses an underground irrigation device including two pieces of pipe connected at right angles by a shutoff valve. One of the pipes is designed for connection to a hose, and the other for insertion into soil to be irrigated. The latter pipe is provided with a water outlet and ground cutting teeth at its lower end for facilitating insertion into the soil to be treated, and may be equipped with a nozzle if desired. A stream of water or other medium emerges only from the lower, or nozzle end of the ground insertable pipe so as to aid in penetration of the pipe as well as irrigating the soil. Further, U.S. Pat. Nos. 1,893,707, issued Jan. 10, 1933, and U.S. Pat. No. 1,964,064, issued June 26, 1934, both to G. C. Karshner, disclose an apparatus for underground fertilization of tree roots and the like, which are similar to the device discussed above in that a treating medium emerges only from a lower end of a longitudinally extending pipe, or tube, inserted into a soil to be treated. In U.S. Pat. No. 1,893,707, a hand-operated shutoff squeeze lever can be employed to control the flow of a liquid fertilizer into the soil being treated.
U.S. Pat. No. 2,850,992, which issued Sept. 9, 1958 to J. J. Hooper et al, discloses a garden watering tool which includes a plurality of prongs insertable into soil to be irrigated, but in which the irrigating medium flows out of a downwardly extending pointed tip of each prong in the same manner as in the devices discussed above. U.S. Pat. No. 3,326,306, issued June 20, 1967, to B. B. Weir, discloses a water spade, which, although primarily intended as a spade in which a fluid medium assists in digging, will inherently irrigate the soil in which the spade is being used.
U.S. Pat. No. 1,058,138, issued Apr. 8, 1913, to A. C. Balou, discloses a device primarily intended for preparing soil for transplanting purposes and in which an inner sleeve slidably disposed in an apertured outer sleeve causes a lateral flow of water when the device has been inserted into soil to be treated. A primary difference between this device and those discussed above is that the irrigating flow is lateral of the ground insertable pipe member as opposed to the axial flow obtained by the others. In a like manner, U.S. Pat. No. 3,900,962, issued Aug. 26, 1975 to S. F. Chan, discloses a fertilizing apparatus which is wind driven for metering air and collected rain directly into soil to be treated. Like the device discussed immediately above, the flow of fluid from the portion of the device inserted into soil being treated is lateral, as opposed to axial, of the inserted portion.
U.S. Pat. No. 2,875,713, issued Mar. 3, 1959, to W. M. Shoffner, discloses a root feeder combining both lateral and axial discharge from a ground insertable portion. This combined flow, however, is constant in both directions, instead of the more desirable primarily axial flow drain during insertion and primarily lateral flow after insertion.
U.S. Pat. Nos. 2,336,522, issued Dec. 14, 1943, to J. K. Aiman, and U.S. Pat. No. 3,659,536, Issued May 2, 1972, to R. B. White, overcome the principal drawback of the device discussed immediately above by controlling axial and lateral flow as desirable. To accomplish this end, the former device employs separate control valves disposed in a portion of the apparatus which remains above ground, while the latter device permits axial flow at all times, but has a sliding sleeve valve disposed in the ground penetrating portion thereof for blocking and unblocking the lateral apertures. A principal disadvantage of this construction is that the sliding parts can become clogged by dirt during the ground penetrating operation.